Numerous case reports have demonstrated lead poisoning with potentially fatal consequences can result from retained lead projectiles following firearm injuries. To assess the impact of retained projectiles on subsequent lead exposure, one cannot rely on self-selected cases presenting with symptoms of lead intoxication. The long-term goal of this project is to reduce the morbidity associated with body lead burden as a result of retained bullets from firearm injuries. The proposed investigation seeks to identify risk factors of elevated blood lead levels for individuals with retained lead bullets, establish appropriate protocols for lead testing, develop indications for bullet removal and provide guidelines for the appropriate management of fragments not removed. The study design included follow-up of 300 patients with retained lead bullets/bullet fragments presenting for acute care of firearm injury at large publicly owned Level 1 Trauma Center. A baseline blood level is measured as soon after patient stabilization as possible and repeated at intervals of 3, 6 and 12 months. Medical history regarding prior firearms injuries and other retained projectiles is taken, along with a screening and risk factor questionnaire to determine other sources of lead (occupational/recreational) to which the patient might have been or at present be exposed. The patient will have K- shell X ray florescence determination of bone lead in the tibia and calcaneus in order to determine past lead exposure not revealed by medical history and risk factor questionnairer. Multivariate models of blood level are made for each patient visit using risk factor and bone lead concentration data. Determinations will be made if changes in blood lead, adjusted for risk factors and bone lead concentration, from one 3 month period to the next can be significantly predicted by the coded location and fragmentation data of projectiles and presence or absence of fractures. The variables of location, fragmentation, fracture and total time during which the projectile was retained in the body will be tested using logistic regression. This will determine odds ratios of elevated lead at various concentrations (greater than 15 mug/dL, greater than 25 mug/dL, greater than 40 mug/dL, etc.) due to these factors. Data will also be analyzed in the framework of the general linear model (GML), with a repeated measure design. Principal interest will be in increasing trend of blood level as a function of fragmentation location, fracture and duration variables.